// version 0.4 

Spry.Data.DataSet.multiFilterFuncs = {};
Spry.Data.DataSet.multiFilterFuncs.and = function(ds, row, rowNumber, filters)
{
	if (filters)
	{
		var numFilters = filters.length;
		for (var i = 0; i < numFilters; i++)
		{
			row = filters[i](ds, row, rowNumber);
			if (!row)
				break;
		}
	}
	return row;
};

Spry.Data.DataSet.multiFilterFuncs.or = function(ds, row, rowNumber, filters)
{
	if (filters && filters.length > 0)
	{
		var numFilters = filters.length;
		for (var i = 0; i < numFilters; i++)
		{
			var savedRow = row;
			row = filters[i](ds, row, rowNumber);
			if (row)
				return row;
			row = savedRow;
		}
		return null;
	}
	return row;
};

Spry.Data.DataSet.prototype.getMultiFilterFunc = function()
{
	var func = Spry.Data.DataSet.multiFilterFuncs[this.getFilterMode()];
	if (!func)
		func = Spry.Data.DataSet.multiFilterFuncs["and"];
	var filters = this.activeFilters;
	return function(ds, row, rowNumber) { return func(ds, row, rowNumber, filters); };
};

Spry.Data.DataSet.prototype.addFilter = function(filterFunc, doApplyFilters)
{
	if (!this.hasFilter(filterFunc))
	{
		if (!this.activeFilters)
			this.activeFilters = [];
		this.activeFilters.push(filterFunc);
	}
	if (doApplyFilters)
		this.applyFilters();
};

Spry.Data.DataSet.prototype.removeFilter = function(filterFunc, doApplyFilters)
{
	var filters = this.activeFilters;
	if (filters)
	{
		var numFilters = filters.length;
		for (var i = 0; i < numFilters; i++)
		{
			if (filters[i] == filterFunc)
			{
				this.activeFilters.splice(i, 1);
				if (doApplyFilters)
					this.applyFilters();
				return;
			}
		}
	}
};

Spry.Data.DataSet.prototype.removeAllFilters = function(doApplyFilters)
{
	var filters = this.activeFilters;
	if (filters && filters.length > 0)
	{
		this.activeFilters = [];
		if (doApplyFilters)
			this.applyFilters();
	}
};

Spry.Data.DataSet.prototype.getFilters = function(filterFunc)
{
	if (!this.activeFilters)
		this.activeFilters = [];
	return this.activeFilters;
};

Spry.Data.DataSet.prototype.applyFilters = function()
{
	if (this.activeFilters && this.activeFilters.length > 0)
		this.filter(this.getMultiFilterFunc());
	else
		this.filter(null);
};

Spry.Data.DataSet.prototype.hasFilter = function(filterFunc)
{
	if (!this.activeFilters && this.activeFilters > 0)
	{
		var filters = this.activeFilters;
		var numFilters = filters.length;
		for (var i = 0; i < numFilters; i++)
		{
			if (filters[i] == filterFunc)
				return true;
		}
	}
	return false;
};

Spry.Data.DataSet.prototype.getFilterMode = function()
{
	return this.filterMode ? this.filterMode : "and";
};

Spry.Data.DataSet.prototype.setFilterMode = function(mode, doApplyFilters)
{
	var oldMode = this.getFilterMode();
	this.filterMode = mode;
	if (doApplyFilters)
		this.applyFilters();
	return oldMode;
};